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11.
IntroductionWe investigated falls at a metropolitan airport to determine fall incidence, identify potential causes of these falls, and suggest opportunities for mitigation.MethodsWe used deidentified incident reports of all falls requiring EMS response that occurred at the airport during 2009 and 2010.ResultsOn average, one fall occurred every 2.3 days. Ninety-six percent (96%) of falls occurred in terminals. Of all falls, 44% occurred on escalators, making escalators the most common location. Seventy-two percent (72%) of fallers were females; 43% were ≥ 65 years; 92% of all falls resulted in a documented injury; 37% of falls resulted in transport to hospital emergency departments. Escalator fall risks include carrying bags (due to changes in baggage fees), using cells phones, not using handrails, and compromised strength and balance.Conclusions and ImpactDiverting at-risk passengers to elevators could significantly reduce the overall falls. Interventions targeting escalator falls have the greatest promise for reducing falls at this airport.  相似文献   
12.

Heavy metals are the most dangerous hazards affecting aquatic biota in Egypt specially the Nile Tilapia, Oreochromis niloticus, which is an important species in commercial fisheries. Some areas were not fully studied to screen the hazards that may affect this economic fish. Therefore, the present study aimed to evaluate the potential hazards of heavy metals on O. niloticus in Al-Gharbiya Governorate in the Middle delta of Egypt. Water and fish samples were collected from Al-Qased canal, Kafr El-Zayaat Nile, El-Maash canal in Al-Gharbiya Governorate plus a reference site which is a fish farm at the Faculty of Agriculture, Damietta University, Damitta Governorate, Egypt. The results showed a significant increase (p?<?0.05) in the lead, zinc, magnesium, manganese, and copper levels while showed a significant decrease (p?<?0.05) in the iron level in the water from all the investigated areas. Cadmium level was significantly high (p < 0.05) in Kafr El-Zayaat Nile and EL-Maash canal only. These metals were also accumulated in the fish livers and gills. Consequently, ALT and AST activities and creatinine level were significantly (p?<?0.05) high in all the investigated areas. Histopathological examination revealed cytoplasmic and nuclear degeneration in the hepatocytes in all the investigated areas. Renal glomeruli and Bowman’s capsule were not completely intact in Al-Qased and El-Maash canals while conspicuous shrinkage of the glomeruli was determined in Kafr El-Zayaat Nile. Furthermore, slight damage in the secondary lamellae was detected in the gill from Al-Qased canal while in the other areas appeared vacuolated or destructed. Finally, spleen sections of fish from different sites showed the absence of melanin pigments and some vacuoles. In conclusion, the Nile Tilapia, Oreochromis niloticus, is affected by the toxic effects of the heavy metals in Al-Gharbiya Governorate in Egypt and this gives an alarm and should be taken into consideration.

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13.
Median atmospheric concentrations of Pb, Br, S, As, Se, and particulate matter (PM) decreased, and median concentrations of Sb, Cu, Zn, Fe, Ca, Cr and Ba increased in urban aerosol in downtown Budapest between 1996 and 2002. The changes in Pb and Br concentrations were unambiguously attributed to the phasing out of leaded gasoline. The increments were mainly related to and explained by non-exhaust vehicular emissions. The mechanical wear of asbestos-free brake linings of road vehicles contributed to the concentration of Cu and Sb on average by 69% and 66%, respectively in the PM10 size fraction. Tire rubber abrasion was a major source for atmospheric Zn; on average, non-crustal sources accounted for 67% of Zn in the PM10 size fraction. Contribution of the tire wear component to the PM10 mass was estimated to be 6% at most, while its contribution to organic aerosol was of the order of 15%.  相似文献   
14.
The present investigation was undertaken to study the induction of DNA damage by lead chloride (PbCl(2)) in freshwater climbing perch Anabas testudineus using alkaline single cell gel electrophoresis (comet assay). Based on the LC(50) values of lead chloride of A. testudineus three different concentrations viz., 0.1, 1.0 and 2.0 mg/L were selected to expose fish. The DNA damage was observed in the gill, kidney and liver tissue as the percentage of DNA in comet tails and comet heads in the tissue of the exposed fish. DNA damage at different concentrations showed sensitivity to particular tissue. The liver tissue exhibited significantly (p < 0.01) higher DNA damage, followed by kidney and gill. However, the DNA damage was found to be dose dependent; at 2 mg/L of PbCl(2) the tail and head DNA of liver tissue were 57.84% and 39.49%, in kidney tissue the values were 52.36% and 44.97% whereas in gill tissue the values were 48.86% and 48.96% respectively. The current study explored the utility of the comet assay for in vivo laboratory studies using A. testudineus species for screening the genotoxic potential of lead chloride.  相似文献   
15.
To enhance the production of lipopeptide antibiotic iturin A, nutrient contents of the culture mediums were investigated in both submerged and biofilm fermentations. As a carbon source maltose and as nitrogen source, fish protein was used. In submerged fermentation maltose uptake was found lower (12%) compared to biofilm fermentation (15%) that was associated with higher cellular growth in biofilm. However, requirement of nitrogen (fish protein) concentration was found similar in both submerged and biofilm fermentations. Production of iturin A in submerged fermentation with 12% maltose and 5% fish protein was 4450 mg/L, and in biofilm fermentation it was 5050 mg/L when 15% maltose and 5% fish protein was used.  相似文献   
16.
Profenofos and trizaophos (organophosphates) carbofuran and carbaryl (carbamates) are among the major toxicants polluting freshwater bodies, as well as exerting a significant effect on the health of fish. In this study, the 96 h LC50 of the most commonly used organophosphates and carbamates was determined in one of the indigenous fish species, Labeo rohita fingerlings. Pesticides were applied to fingerlings that had been grown under optimized standard conditions under a maintained static bioassay system. Probit analysis was used for the determination of LC50 values, which were ascertained as 6.64, 0.32, 1.4, and 8.24 mg/L for triazophos, profenofos, carbofuran, and carbaryl, respectively. Acute toxic stress was noted with fish exhibiting behavioral toxicity including suffocation, lying on the bottom, erratic swimming, lethargy and downward movements, and gulping prior to mortality.  相似文献   
17.
Environmental Geochemistry and Health - This study aimed to determine the status of groundwater contamination with faecal coliform and nitrate in the rural areas of Mardan district, Pakistan. Both...  相似文献   
18.
In this paper, the inhibition of methanogens by phenol in coal gasification wastewater(CGW)was investigated by both anaerobic toxicity tests and a lab-scale anaerobic biofilter reactor(AF). The anaerobic toxicity tests indicated that keeping the phenol concentration in the influent under 280 mg/L could maintain the methanogenic activity. In the AF treating CGW,the result showed that adding glucose solution as co-substrate could be beneficial for the quick start-up of the reactor. The effluent chemical oxygen demand(COD) and total phenol reached1200 and 100 mg/L, respectively, and the methane production rate was 175 m L CH4/g COD/day.However, if the concentration of phenol was increased, the inhibition of anaerobic micro-organisms was irreversible. The threshold of total phenol for AF operation was 200–250 mg/L. The extracellular polymeric substances(EPS) and particle size distribution of anaerobic granular sludge in the different stages were also examined, and the results indicated that the influence of toxicity in the system was more serious than its effect on flocculation of EPS. Moreover, the proportion of small size anaerobic granular sludge gradually increased from10.2% to 34.6%. The results of high through-put sequencing indicated that the abundance of the Chloroflexi and Planctomycetes was inhibited by the toxicity of the CGW, and some shifts in the microbial community were observed at different stages.  相似文献   
19.
This experiment was conducted to study the genotoxic potentials of sodium arsenite (NaAsO2) in freshwater fish Oreochromis mossambicus by using alkaline comet assay and micronucleus (MN) test. Fish were exposed to three different concentrations (3 ppm, 28 ppm and 56 ppm) of arsenic and gill, liver and blood tissue samples were collected after 48 h, 96 h and 192 h of exposure. Arsenic exposure induced DNA damage in all tissues examined in a concentration dependent manner. A significant (< 0.05) increase in the comet tail DNA (%) of the exposed fish liver, gill, and blood was observed after 48 h and 96 h of exposure, but a decline in DNA damage was recorded in all the tissues at all the three concentrations studied after 192 h of exposure. Liver tissue exhibited significantly (< 0.05) higher DNA damage at all the concentrations examined, followed by gill and blood. Higher liver tail DNA (51.38 ± 0.21%) refers that it is more prone to injury to arsenic toxicity than the gill and blood. In blood samples arsenic induced micronucleus formation in a concentration dependent manner and highest (5.8 ± 0.46%) value was recorded in 56 ppm after 96 h of exposure, whereas, it was decreased after 192 h of exposure at all the three concentrations of NaAsO2 examined which refers to the DNA repairing ability of fish to arsenic toxicity. The results of this study depict the genotoxic potentials of arsenic to fish which in turns provide insight on advanced study in aquatic toxicology.  相似文献   
20.
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